NEARLY one in four women develops depression during pregnancy, according to a leading psychiatrist.

Dr Joanne Fenton said some symptoms of depression are unique to pregnancy, including not looking forward to the baby, feeling worthless and guilty about being a parent and having obsessive thoughts about harming the baby.

They can also include a woman feeling suicidal and feeling that the baby would be better off with another mother.

She said it is important that healthcare staff remain alert and screen a woman for possible symptoms of depression at different stages of pregnancy as well as after the birth such as when she brings her baby for jabs.

Women are also more at risk of being admitted to a psychiatric unit in the six weeks after giving birth than at any other time in their lives.

Dr Fenton, of the Coombe Hospital in Dublin, said more than half of women who suffer post-natal depression have had some form of depression during their pregnancy.

She described perinatal depression, affecting a woman during pregnancy and after the birth, as a common problem.

Among the risk factors is an unplanned pregnancy, lack of a partner, ill health in the baby and difficulty breastfeeding, she wrote in the GP journal 'Forum'.

These can lead to general symptoms of depression such as feelings of hopelessness, lack of sleep and poor appetite.

It is important to identify women with perinatal depression, and there tends to be a "high index of suspicion" because pregnancy and birth are major life events.

Women should be screened at their first hospital appointment and at weeks 28 to 32 in the pregnancy as well as at the six-week check-up and after the birth.

There should be further checks when the mother brings the baby to the GP for vaccinations, said Dr Fenton.

If patients are not treated for depression in pregnancy, it can lead to a risk of problems such as dangerously high blood pressure, substance abuse and difficulty bonding with the child.

If a woman is identified early and receives treatment, these risks can be reduced, she pointed out.